JP5063292B2 - Diagnostic imaging support device - Google Patents

Description

  The present invention measures image data including a lung field of a subject, calculates a portion whose shape has changed in the image data due to an action such as a lung disease or a sign thereof, and performs image diagnosis performed by a doctor on the calculated information. The present invention relates to an image diagnosis support apparatus presented as support information.

  A user such as an interpreting physician operates the information display means as follows. In the list of the plurality of examination information displayed on the information display means, the examination information next to the next line below the predetermined examination information corresponding to the diagnosis target medical image displayed on the image display means. Displays the next corresponding image. Prior to this display, at least a part of the next image is first read from the image storage means and temporarily stored, and the rest of the next image is not read by the end of the input of the diagnosis result. If there is, read the rest. In parallel with this reading, or after that, the diagnosis target image displayed on the image display means is controlled to be switched to the next image that has been read first and displayed. As a result, the examination information to be interpreted in advance is automatically displayed in a list, and the examination information displayed in the list is displayed at a high speed with a simple key operation in order to display medical diagnostic images to be examined continuously. can do. There has been proposed a medical image diagnostic system capable of efficiently performing interpretation work without imposing a burden on a user such as an interpretation doctor (for example, Patent Document 1).

JP 2006-178773 A.

  In recent years, it has been known that accumulation of asbestos inhaled in a subject in an image diagnosis appears as an abnormality in the thickness of the chest wall (also referred to as lung wall).

  In order to accurately observe an abnormality in the thickness of the chest wall, there is an unsolved problem that it is difficult to distinguish whether it is caused by a pathological change of the chest wall or a partial volume effect by simple interpretation.

  An object of the present invention is to provide an image diagnosis support apparatus that can accurately observe an abnormality in the thickness of the chest wall.

  The object is to extract an image acquisition unit that acquires a tomographic image including a lung region of a subject, an image display unit that displays the acquired tomographic image, and an inner side of a rib included in the tomographic image as a chest wall region. A chest wall region extracting means; a thickened portion measuring means for measuring a thickened portion of a lung wall region with reference to the extracted chest wall region; a chest wall contour extracting means for extracting a chest wall contour of a tomographic image adjacent to the tomographic image; Image generating means for generating a superimposed image of the measured thickened portion of the lung wall region and the chest wall contour of the adjacent tomographic image; and display control means for controlling display of the generated superimposed image on the image display means; This is achieved by having

  ADVANTAGE OF THE INVENTION According to this invention, the diagnostic imaging assistance apparatus which can observe the abnormality of the thickness of a chest wall with a sufficient precision can be provided.

  The best mode for carrying out the present invention will be described below with reference to the accompanying drawings. Note that components having the same function are denoted by the same reference symbols throughout the drawings for describing the embodiment of the invention, and the repetitive description thereof is omitted.

Further, the following technical terms (1) and (2) used in the specification of the present application are defined to have special meanings in addition to the original lexical meaning.
(1) The “pure chest wall region” refers to a chest wall region when it is assumed to be healthy, and indicates a region to the end of the thin film on the extreme inner side of the rib.
(2) The “chest wall region” is a region obtained by adding a thickened portion measured by the thickened portion measuring means to the “pure chest wall”.

  FIG. 1 is a hardware configuration diagram showing a configuration example of the entire diagnostic imaging support apparatus according to the present invention.

  The diagnostic imaging support apparatus 10 is connected to a medical imaging apparatus 2 that captures an image of a subject via a network such as LAN3. The medical image capturing apparatus 2 is described as an X-ray CT apparatus as an example, but is configured by an apparatus capable of capturing an image of a subject (preferably a three-dimensional image) such as an MR apparatus or an ultrasonic imaging apparatus.

  The diagnostic imaging support apparatus 10 is mainly a central processing unit (CPU) 11 as a control device that controls the operation of each component, and a main memory 12 that stores a control program for the device and serves as a work area when the program is executed. And a magnetic disk 13 in which various application software including programs for processing such as operating system (OS), peripheral device drive, and chest wall thickness measurement are stored, and display for temporarily storing display data A memory 14, a monitor 15 such as a CRT monitor or a liquid crystal monitor that displays an image based on data from the display memory 14, a mouse 17 as a position input device, and a mouse on the monitor 15 by detecting the state of the mouse 17 Consists of a controller 16 that outputs signals such as the pointer position and mouse 17 status to the CPU 11, a keyboard 18, and a bus 19 that connects the above components. It is.

  The CPU 11 reads the program from the magnetic disk 13, loads it into the main memory 12, and executes it.

  In FIG. 1, the magnetic disk 13 is connected as a storage device other than the main memory 12, but a hard disk drive or the like may be connected in addition thereto.

  Next, the flow of processing of the first embodiment will be described with reference to FIG.

(Step 20)
An operator such as a doctor displays a CT image or an MRI image on the monitor 15 and operates the mouse 17 to set points as indicated by reference numerals 1a, 1b, 2a, and 2b as shown in FIG. The measurement range for extracting the lung wall of (i.e., Ψs, Ψs + 1 is set) is set. This measurement range may be automatically set by a computer as will be described later.

(Step 21)
The CPU 11 extracts the lung wall along the set measurement range. As shown in FIG. 4, the chest wall is extracted with the chest wall as the inner side of the rib 40. The CPU 11 may extract a rib with a high CT value and perform spline interpolation on the inside to form a chest wall. Alternatively, the CPU 11 may extract the chest wall by threshold processing by determining the threshold value so that the inside of the rib is extracted as the chest wall.

(Step 22)
The CPU 11 determines whether there is a fat region (reference numeral 50 in FIG. 5) in close contact with the lung wall. In this case, measurement is performed from one end of the fat region. Since the fat region has a small CT value, the fat region exists in the order of the chest wall region, the region with a small CT value, and the region with a relatively large CT value (thickened portion). If the fat area exists, the CPU 11 proceeds to step 27, and if the fat area does not exist, the CPU 11 proceeds to step 23.

(Step 23)
The CPU 11 measures the thickness of the thickened part from the lung wall. In this case, the thickness is measured in the direction perpendicular to the chest wall.

(Step 24)
The CPU 11 determines whether or not the measurement in the measurement area is finished. If the measurement has not been completed, the CPU 11 proceeds to step 22, and if the measurement has been completed, the CPU 11 proceeds to step 25.

(ステップ27)
CPU11は、肺壁からの脂肪領域を除いて、肥厚部の厚さを計測する。ここでは厚さは、胸壁に垂直方向に計測する。CPU11は、胸壁から肥厚部の端までの長さから脂肪部の長さを差し引いて、肥厚部の厚さとする。あるいは、CPU11は、脂肪領域の端から肥厚部の端までを肥厚部の厚さとしても同じである。
また、CPU11は、θiとΨsにスライス厚方向の角度を乗じて、立体角としての割合を求めてもよい。 (Step 25)
CPU11 identifies the region where the lung wall thickness is thicker than the preset thickness and other regions, and calculates the sum of angles from the lung field center (= Σθi)
(Step 26)
The CPU 11 obtains and displays (for example, reference numeral 51 in FIG. 5) a ratio (percentage) of a region thicker than the set thickness of the lung wall (for example, 5 mm, but can be changed from the GUI).
If the CPU11 is larger than a preset ratio (for example, 50%, but can be changed from the GUI), a message stating that "asbestos accumulation is more than 50% of the perimeter of the lung" is displayed. . The message may be displayed, sounded, or vibrated. In short, it is sufficient that a message is transmitted to the five senses of the operator. In this paper, the term “presentation” is a collective term for the CPU 11 to transmit information to the operator through display, voice, and the like.
Further, the examination object may be a single CT image (1 slice) or a plurality of CT images (N slices) continuous in the body axis direction of the subject. CT images (N slices) may be used. The ratio in 1 slice and the ratio in N slice are as follows.

(Step 27)
The CPU 11 measures the thickness of the thickened portion excluding the fat region from the lung wall. Here, the thickness is measured perpendicular to the chest wall. The CPU 11 subtracts the length of the fat portion from the length from the chest wall to the end of the thickened portion to obtain the thickness of the thickened portion. Alternatively, the CPU 11 has the same thickness from the end of the fat region to the end of the thickened portion as the thickness of the thickened portion.
Further, the CPU 11 may obtain a ratio as a solid angle by multiplying θi and Ψs by an angle in the slice thickness direction.

(Step 28)
The CPU 11 determines whether to display the influence of the partial volume effect. The presence or absence of this display may be set by the operator using the mouse 17 or the keyboard 18, or may be determined in advance when the program is executed. As a result of this determination, the CPU 11 proceeds to step 29 if the influence of the partial volume effect is to be checked, and ends the process if the influence of the partial volume effect is not checked.

(Step 29)
As shown in FIGS. 10 and 11, the CPU 11 determines whether or not the ratio of the convex i region in the image between the pure chest walls WS-1 and WS + 1 of the slices S-1 and S + 1 is ratio> constant. To do. As a result of the determination, the CPU 11 proceeds to step 2A if the ratio> constant, and proceeds to step 2B if the ratio ≦ constant.

(Step 2A)
The CPU 11 processes the thickened portion area affected by the partial volume effect so that the thickened portion area is deleted as shown by convex 2 and convex 3 in FIG. The area is superimposed on the image and the process is terminated.

(Step 2B)
The CPU 11 has a thickened area that is not affected by the partial volume effect, and the thickened area has several different colors (for example, severe red, mild yellow, and blue with no worries), as shown by the convex 1 in FIG. Or the like, and display a warning message or display a warning message, superimpose the processed thickened region on the image, and terminate the processing.

According to the present embodiment, it is possible to present the distribution status of diseases including asbestos and to take into account the influence of the partial volume effect, so that an abnormality in the thickness of the chest wall can be accurately observed. A unique effect of the present embodiment is that a disease distribution situation can be presented by a characteristic one-slice CT image or a plurality of continuous CT images.
Next, another method for quantifying the thickened portion according to the second embodiment will be described. The operator may select and use the quantification of the thickened portion of the first embodiment or the second embodiment as appropriate. A processing flow of the second embodiment will be described with reference to FIG.
(Step 60)
The operator displays a CT image or an MRI image on the monitor 15 and operates the mouse 17 to set points as indicated by reference numerals 1a, 1b, 2a, 2b as shown in FIG. Set the measurement range for extracting (and therefore set LNG1, LNG2). This measurement range may be automatically determined by a computer as will be described later. CPU11 calculates | requires the length (= LNG1 + LNG2) along the lung wall in the designated lung wall area | region.

(Step 61)
The CPU 11 extracts the lung wall along the set measurement range. Similar to the first embodiment, as shown in FIG. 4, the chest wall is extracted using the chest wall directly inside the rib 40 as a chest wall. The CPU 11 may extract a rib with a high CT value and perform spline interpolation on the inside to form a chest wall. Alternatively, the CPU 11 may extract the chest wall by threshold processing by determining the threshold value so that the inside of the rib is extracted as the chest wall.

(Step 62)
The CPU 11 determines whether or not there is a fat region (reference numeral 80 in FIG. 8) close to the lung wall. Since the fat region has a small CT value, the fat region is present in the order of the chest wall region, the region having a small CT value, and the region having a relatively large CT value (thickened portion). If the fat region exists, the process proceeds to step 67. If the fat region does not exist, the process proceeds to step 63.

(Step 63)
The CPU 11 measures the thickness of the thickened part from the lung wall. The thickness of the thickened part is measured perpendicular to the chest wall.

(Step 64)
The CPU 11 determines whether or not all the measurements without the measurement area have been completed.
If all measurements have not been completed, the process proceeds to step 62, and if all measurements have been completed, the process proceeds to step 65.

(Step 65)
The CPU 11 calculates the sum of lengths (= ΣLi) along the ash wall in the region thicker than the specified thickness.

(ステップ67)
CPU11は、肺壁からの脂肪領域を除いて(脂肪の端からの)、肥厚部の厚さを計測する。厚さは、胸壁に垂直方向に計測する。
また、CPU11は、LiとLNGsにスライス厚を乗じて、面積としての割合を求めてもよい。 (Step 66)
The CPU 11 obtains the ratio (percentage) of the area thicker than the specified thickness and displays it (for example, reference numeral 81 in FIG. 8). In this case, P1 = 100 × (L1 + L2 + L3) / LNG1 in the left lung field and P2 = 100 × L4 / LNG2 in the right lung field. If the obtained ratio is larger than the preset ratio, for example, a message that “the accumulation of asbestos is an area of 50% or more of the perimeter of the lung” is displayed. The message may be presented to the operator as in the first embodiment.
Further, the examination target may be a single CT image (1 slice) or a plurality of CT images (N slices) continuous in the body axis direction of the subject. The ratio in 1 slice and the ratio in N slice are as follows.

(Step 67)
The CPU 11 measures the thickness of the thickened portion excluding the fat region from the lung wall (from the end of the fat). Thickness is measured perpendicular to the chest wall.
Further, the CPU 11 may obtain a ratio as an area by multiplying Li and LNGs by a slice thickness.

(Step 68)
The CPU 11 determines whether to display the influence of the partial volume effect. The presence or absence of this display may be set by the operator using the mouse 17 or the keyboard 18, or may be determined in advance when the program is executed. As a result of this determination, the CPU 11 proceeds to step 69 if the influence of the partial volume effect is to be checked, and ends the process if the influence of the partial volume effect is not checked.

(Step 69)
As shown in FIGS. 10 and 11, the CPU 11 determines whether or not the ratio of the convex i region in the image between the pure chest walls WS-1 and WS + 1 of the slices S-1 and S + 1 is ratio> constant. To do. As a result of this determination, the CPU 11 proceeds to step 6A if the ratio> constant, and proceeds to step 6B if the ratio ≦ constant.

(Step 6A)
The CPU 11 processes the thickened portion area affected by the partial volume effect so that the thickened portion area is deleted as shown by convex 2 and convex 3 in FIG. The area is superimposed on the image and the process is terminated.

(Step 6B)
The CPU 11 processes the thickened portion area, which is not affected by the partial volume effect, as shown by the convex 1 in FIG. The display is superimposed and the process ends.
According to the present embodiment, it is possible to present the distribution status of diseases including asbestos and to take into account the influence of the partial volume effect, so that an abnormality in the thickness of the chest wall can be accurately observed. The unique effect of this embodiment is that it can present the disease distribution status in a characteristic 1-slice CT image, a continuous multi-slice CT image, or a non-continuous multi-slice CT image, Intuitive numerical information is presented to the operator of the sheath area and angle.

  Next, processing according to the third embodiment will be described with reference to FIG.

  The automatic measurement range determination method described in step 20 of the first embodiment and step 60 of the second embodiment will be described.

  First, the CPU 11 obtains the end point 91 of the left lung field. Note that the end point 91 of the left lung field is not limited to one point, and may be in the vicinity thereof. A point 911 farthest upward from the end point 91 of the left lung field and a point 912 farthest downward from the end point 91 of the left lung field are obtained, and a range between the points 911 and 912 is set as a measurement range.

  Similarly for the right lung field, the CPU 11 obtains the end point 92 of the right lung field. Note that the end point 92 of the right lung field is not limited to one point, and may be in the vicinity thereof. A point 921 farthest upward from the end point 92 of the right lung field and a point 922 farthest downward from the end point 92 of the right lung field are obtained, and a region between the points 921 and 922 is set as a measurement range. For example, if Ri is the length from the center point of the right lung field to the lung wall, the length of the lung wall in the range determined by the last drawing is L = ΣRi × dθ (dθ is a minute angle) 5 mm or more thick lung The length of the wall is L ′ = ΣRi ′ × dθ ratio (%) is 100 × L ′ / L. In the case of the left lung field, it is obtained in the same manner as the right lung field.

  According to the present embodiment, it is possible to present the distribution status of diseases including asbestos and to take into account the influence of the partial volume effect, so that an abnormality in the thickness of the chest wall can be accurately observed. A unique effect of this embodiment is that the measurement range is automatically set, so that the operator can save labor and trial and error for setting the measurement range.

Next, processing according to the fourth embodiment will be described with reference to FIGS.
FIGS. 13 and 14 show a method for obtaining the ratio of the thickened region when the partial volume effect is excluded.

(Step 130)
The CPU 11 clears the parameters of the sum total value Sum and counter i of the convex area to zero.

(Step 131)
The CPU 11 determines whether the ratio of the convex i region between the slice walls S−1 and S + 1 between the chest walls WS−1 and WS + 1 is ratio> constant. As a result of the determination, the CPU 11 proceeds to step 132 if the ratio> constant, and proceeds to step 133 if the ratio ≦ constant.

(Step 132)
The CPU 11 adds the length Li (see FIG. 14) along the chest wall of the convex i region to Sum.

(Step 133)
The CPU 11 determines whether or not all thickening areas (projections) have been specified. As a result of the determination, if the designation is finished, the CPU 11 proceeds to step 134, and if not designated, proceeds to step 136.

(Step 134)
The CPU 11 calculates the ratio of the Sum convex area.
Required ratio [%] = 100 x Sum / LL
LL is the chest wall length excluding the convex portion of the defined (or set) range. In the pure chest wall length excluding the convex portions in the range of 1a to 1b and 2a to 2b in FIG. 14, the left and right lung field regions are LNG_R and LNG_L, respectively.
For example, the ratio of one slice in the right lung field is a value obtained by dividing ΣLi (ratio of convex i _out > constant) by the chest wall length of 1a to 1b.
For example, in the case of FIG. 14, if the constant is 40%, ΣLi (ratio of convex i _out > 40%) becomes the chest wall length L2.
A thickened part thicker than a predetermined thickness (for example, 5 cm) can be easily diagnosed by coloring it. Specifically, a thickened portion thicker than a predetermined thickness (for example, 5 cm) is displayed in red, for example, and a portion that enters between adjacent pure chest walls is displayed in “light red”, and a portion that does not enter is dark. When displayed in red, it becomes easier to grasp the thickened part in three dimensions.

(Step 135)
The CPU 11 stores the obtained ratio in the display memory 14 and stores it in the magnetic disk 13.

(Step 136)
CPU 11 adds 1 to counter i and proceeds to step 131.

  FIG. 15 shows the chest wall excluding the convex portion. The inner wall of the rib is spline interpolated to find the chest walls 150A and 150B. That is, D1 and D2 in FIG. 15 are the thicknesses of the convex portions.

  In Fig. 16 (a), threshold processing is performed along a straight line (dotted line) perpendicular to the reference line of the chest wall, and radial scanning is performed from the center of gravity of the left and right lung fields, and threshold processing to the ribs is performed. The case where a chest wall was calculated | required is shown.

  FIG. 16B shows a case where threshold processing is performed in an area parallel to the reference line of the chest wall, and the chest wall is obtained by threshold processing that is measured from the ribs and does not have a parallel region to the reference line.

  According to the present embodiment, it is possible to present the distribution status of diseases including asbestos and to take into account the influence of the partial volume effect, so that an abnormality in the thickness of the chest wall can be accurately observed.

  In addition, if the graph is generated as shown in Fig. 17 (a) and superimposed on the MIP image or Latham image created from the CT image and displayed as shown in Fig. 17 (a), the slice position of the thickened part can be easily grasped. Become.

  Next, processing according to the fifth embodiment will be described.

  When not exceeding the reference value of the thickness of the chest wall or exceeding the reference value of the thickness of the chest wall instead of being presented in the message described in step 26 of the first embodiment and step 66 of the second embodiment, the region is colored red, etc. Display on CRT15.

  According to the present embodiment, it is possible to present the distribution status of diseases including asbestos and to take into account the influence of the partial volume effect, so that an abnormality in the thickness of the chest wall can be accurately observed. A unique effect of the present embodiment is that the CT image is displayed in color, so that the operator can intuitively grasp the anatomical position such as asbestos accumulation.

  The preferred embodiments of the medical image display apparatus according to the present invention have been described above, but the present invention is not limited to such examples. It will be apparent to those skilled in the art that various changes or modifications can be conceived within the scope of the technical idea disclosed in the present application, and these are naturally within the technical scope of the present invention. Understood.

Schematic which shows the example of whole structure of the image diagnosis assistance apparatus of this invention. 3 is a flowchart showing a flow of processing of the first embodiment of the diagnostic imaging support apparatus. FIG. 3 is an explanatory diagram showing an example of setting operation of the measurement range in FIG. FIG. 3 is an explanatory diagram of a calculation example of the chest wall in FIG. FIG. 3 is an explanatory diagram showing a display example of distribution measurement in FIG. 10 is a flowchart showing a flow of processing of the second embodiment of the image diagnosis support apparatus. FIG. 7 is an explanatory diagram showing an example of setting operation of the measurement range in FIG. FIG. 7 is an explanatory diagram showing a display example of the distribution measurement in FIG. Explanatory drawing which shows the principle of a process of 3rd Embodiment of the said image diagnosis assistance apparatus. Explanatory drawing which shows the thickening part area | region of the process of 4th Embodiment of the said image diagnosis assistance apparatus. Explanatory drawing which shows the principle of a process of 4th Embodiment of the said image diagnosis assistance apparatus. Explanatory drawing which shows the example of a display of the parameter setting of the process of 4th Embodiment of the said image diagnosis assistance apparatus. Explanatory drawing which shows the flowchart of the process of 4th Embodiment of the said image diagnosis assistance apparatus. Explanatory drawing which shows the partial part removal of the process of 4th Embodiment of the said image diagnosis assistance apparatus. Explanatory drawing which shows the one aspect | mode of the display of the result image of the process of 4th Embodiment of the said image diagnosis assistance apparatus. FIG. 16 is an explanatory diagram showing a display mode different from FIG. Explanatory drawing which shows the aspect of a display different from FIG.

Explanation of symbols

  10 diagnostic imaging support device, 11 CPU, 12 main memory, 13 magnetic disk, 14 display memory, 15 monitor, 16 mouse controller, 17 mouse, 18 keyboard, 19 common bus.

Claims (4)

Image acquisition means for acquiring a tomographic image including a lung region of the subject;
A chest wall region extracting means for extracting the inside of the rib included in the tomographic image as a chest wall region;
A thickened portion measuring means for measuring a thickened portion of the lung wall region based on the extracted chest wall region;
A chest wall contour extracting means for extracting a chest wall contour of an adjacent tomographic image adjacent to the tomographic image;
Image generating means for generating a superimposed image of the thickened portion of the measured lung wall region and the chest wall contour of the adjacent tomographic image;
Display means for displaying the generated superimposed image;
An image diagnosis support apparatus comprising: The ratio of the thickened portion of the lung wall region measured by the thickened portion measuring unit is included between the two chest wall contours extracted by the chest wall contour extracting unit in each of two adjacent tomographic images. 2. The image diagnosis support apparatus according to claim 1, wherein a message is generated when either the ratio not included or the ratio not included is calculated and the ratio not included is greater than a predetermined value. Of the thickened portion of the lung wall region, thicken a portion where the ratio not included between the two chest wall contours extracted by the chest wall contour extracting means in each of two adjacent tomographic images is larger than a preset value. The image diagnosis support apparatus according to claim 1, further comprising a thickened part re-measurement unit that re-measures the part.   The image diagnosis support apparatus according to claim 3, further comprising means for calculating a ratio of the thickened portion using a length along the chest wall of the thickened portion remeasured by the thickened portion remeasurement means. .

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